Reciprocating liquid pump



Oct. 11, 1966 C. J. J. JoosTE RECIPROCATING LIQUID PUMP 5 Sheets-Sheet l Filed NOV. 18, 1963 Oct. 11, 1966 c. J. J.JoosTE 3,277,836

- REGIPROCATING LIQUID PUMP Filed Nov. 18, 1963 :5 Sheets-Sheet 2 as "se INVENTOR.

BY MMM j/ @a 4Z/M Oct. 11, 1966 C, J. .LJOOSTE 3,277,836

RECIPROCATING LIQUID PUMP Filed Nov. 18, 1965 5 Sheets-Sheet 5 United States Patent O 3,277,836 RECIPROCATlNG LlQUlD PUMP Christiaan `lakobus Johannes Jooste, 173 Main Road, Somerset West, Cape Province, Republic of South Africa Filed Nov. 18, 1963, Ser. No.y 324,453 Claims priority, application Republic of South Africa, Nov. 22, 1962, 62/4,907; July 10, 1963, eil/3,085 1 Claim. (Cl. 10S- 178) This invention relates to reciprocating liquid pumps. More particularly the invention relates to a liquid pump which is capable of pumping liquid in a substantially continuous stream.

According to the invention there is provided a reciprocating liquid pump which includes a reciprocable member adapted to permit liquid to pass through or around it during its reciprocation, and drive means adapted to impart reciprocal movement to the reciprocable member at such a rate that its acceleration on its return stroke is greater than the deceleration of the liquid being pumped.

Thus, for example, in the case of vertical water pumping such as from a borehole, the acceleration of the reciprocable member during its downward (i.e., its return) `stroke must exceed the acceleration of the water present within the reciprocable member, when acted upon by gravity.

Bias means, for example in the form of a compression coil spring, may conveniently be provided to urge the reciprocable member in the direction of its return stroke.

According to a further feature of the invention, additional bias means, conveniently again in the form of a compression coil spring, may be provided to urge the reciprocable member in the direction of its delivery stroke. The additional bias means may, for example, balance a delivery head. If two opposing bias means are provided then they may conveniently be made adjustable to permit adjustment to suit varying operating conditions. In the ca-se of a borehole pump, the additional bias means may be on surface.

The drive means for imparting reciprocal movement to the reciprocable member may include a pivotally mounted actuating arm, an eccentric or crank arranged to act upon the piv-otally mounted actuating arm, connecting means for operatively connecting the actuating arm to the reciprocable member, and a prime mover for driving the eccentric or crank.

The additional bias means may conveniently be arranged to act on the actuating arm. The actuating arm may be mounted in a casing, and the additional bias means may comprise a spring coacting between the casing and the actuating arm, the spring being provided with adjusting means for adjusting its stiffness. In a particular embodiment, the actuating arm may be in the form of a bell crank lever, the additional bias means being arranged to act upon one arm of the lever and the reciprocable member being connected to the other arm. The drive means may include a prime mover such as an electric motor, an internal combustion engine, a wind-driven prime mover, or the like.

Resilient means may conveniently be incorporated in the connecting means connecting the actuating arm and the reciprocable member for the purpose of damping shock loads on the connecting means and the reciprocable member. The resilient means may be in the form of a tension coil spring.

The connecting means between the actuating arm and the reciprocable member may be in the form of a ilexible element such as a cable or a wire, or a nonilexible element such as a rod. Such an arrangement would be particularly suitable for vertical pumping from a depth, such Patented Oct. 1l, 1966 ice as for pumping water from a borehole or the like, in which case the length of the connecting means may be varied to suit different depths, so that the plunger and cylinder assembly .can be lowered into the borehole or the like.

The reciprocable member may be a hollow barrel member having a liquid flow passage to permit liquid flow through it, and in which there are provided a non-return valve in the liquid ilow passage, and connection means for connecting the hollow barrel member to suction and delivery pipe lines in a manner to permit its reciprocation relative to the suction and ldelivery pipe lines. The connection means for connecting the hollow barrel member to suction and delivery pipe lines may conveniently be telescopic or flexible connections.

Alternatively, the reciprocable member may be a plunger member reciprocable within a housing, a nonreturn valve being arranged to permit ow through or around the plunger member during its reciprocation, and connection means for connecting the housing to suction and delivery pipe lines. The plunger member may conveniently be hollow to provide a liquid flow passage through it, the non-return valve being arranged Within the liquid flow passage and including a valve closure member seatable closably on a valve seat provided, and in which stop means is provided to limit the displacement of the valve closure member.

The non-return valve may be of the ball and seat type or of the ap valve type. Stop means may be provided to limit the displacement of the valve closure member into the open position. For example, in the case of a ilap valve an abutment member of a resilient material may be provided on the back of the flap, which abutment member is arranged to abut against the wall of the liquid iiow passage so as to limit the displacement of the flap and hence its degree of opening.

Alternatively, the non-return valve may comprise a at disc-shaped or ring-like or wafer-like lvalve closure member, which is seatable -closably upon a perforated inlet member arranged across the liquid ow passage.

In cases where the drive means requires time in Iorder to impart reciprocal movement at the required rate to the reciprocable member, such as in the case where the drive means comprises a wind-driven prime mover, a foot valve may be provided across the liquid ow passage, so that liquid may be pumped by volumetric displacement during the period before the reciprocable member acquires the required rate -of reciprocal movement. Once the required rate of reciprocation is attained, the foot valve will remain open and pumping will proceed according to the principle of this invention.

In a particular embodiment, a reciprocating liquid pump according to the invention includes a cylinder barrel; a hollow plunger member reciprocable within the cylinder barrel, and having :a liquid flow passage to permit liquid ow through the plunger member; a non-return valve arranged within the liquid ow passage, and comprising a valve closure member seatable closably on a valve seat provided; stop means to limit the displacement of the valve clos-ure member; bias means arranged to act upon the plunger member to urge it in the direction of its return stroke; drive means which includes an eccentric arranged to act upon a pivotally mounted actuating arm, and a prime mover to ydrive the eccentric; connecting means `to connect the actuating arm operatively to the plunger member; additional bias means arranged to act upon the actuating arm to urge the plunger member in the direction of its delivery stroke; and resilient means incorporated in the connecting means; whereby reciprocable movement may 'be imparted to the plunger member at a rate such that its acceleration during its return stroke is greater than the deceleration of the liquid being pumped.

The invention and the manner n which it may be put into practice, will now be more specifically described by way of example, with reference to the accompanying drawings. It must be understood, however, that the invention is not limited to the specific embodiment shown in the drawings.

In the drawings:

FIGURE l represents a side elevation of the drive means for imparting reciprocal movement -to a liquid pump according to the invention;

FIGURE 2 represents a front elevation of the mounting arrangement of the connecting means between the actuating arm and the reciprocable member;

FIGURE 3 represents a Vertical section through the mounting attachment of FIGURE 2, taken along the line III-III;

FIGURE 4 represents a plan view corresponding7 to FIGURE 3;

FIGURE 5 represents a vertical section through a cylinder barrel and plunger according -to the invention;

FIGURE 6 represents a plan view of the element 66 in FIGURE 5; and

FIGURE 7 represents a side elevation of the drive means for imparting reciprocal movement to a liquid pump according to the invention, viewed from the opposite side from FIGURE 1.

Referring to the drawings, and in particular to FIG- URES l to 4 and FIGURE 7, the reciprocable member of a reciprocating liquid pump according to the invention is provided with reciprocal movement by means of drive means generally indicated as 10. Drive means 10 includes a bell-crank actuating arm 12, mounted for pivotal movement about the axis of pin 14, journalled in the walls of a housing or casing 16. Pivotal movementis irnparted to the actuating arm 12 by the eccentric 18, which is operatively connected to the actuating arm 12 via link 20, `so that rotary movement from a prime mover and applied to the eccentric 18 is converted into up and down reciprocal movement of the limb 12a of the actuating arm 12.

The eccentric 18 is driven by a suitable prime mover such an electric motor or an internal combustion engine. From FIGURE 7 it will be seen that a pulley 110 is provided for driving the eccentric 18. The pulley 110 is in turn driven via a belt 112, which passes over a pulley 113 keyed to a driving shaft 114. The shaft 114 is in turn driven by .an electric motor 116, or if desired an internal combustion engine.

Bias means (being the additional bias means) in the form of a compression coil spring 22 `is provided to act upon the upwardly directed limb 12b of the actuating arm 12, for urging it in a direction so as to cause upward displacement of the limb 12a, thereby urging the reciprocable member of the pump, which is connected to the limb 12a of |the Iactuating arm 12, inthe direction of its delivery stroke. The coil spring 22 is adjustable by means of an adjusting bolt 24.

Connecting means in the form of a cable 26 (see FIG- URE 3) is provided for connecting the actuating arm 12 to the reciprocable member of the pump. The upper portion of the cable 26 is accommodated within a tube 28, which passes through a gland 30 in sliding relationship therewith, into flow pipeline 31. The upper ends of the cable 26 and tube 28 are secured to the actuating arm 12 in the following manner:

The limb 12a of the actuating arm 12 is provided at its extreme end with a U-shaped stirrup member 32, on the two arms of which there are pivotally mounted links 34a and 34b. A yoke 36 is pivotally mounted on the links 34a and 34b. The yoke 36 comprises a nut 36a, to which have been secured, such as by soldering or welding, two laterally projecting socket members 36b, to receive bolts 37.

A grip element 38 for gripping the upper ends of the cable 26 and tube 28 is provided, which comprises an externally threaded shank having a bore 40 of a crosssectional area slightly larger than the cross-sectional area of the cable 26 and in which the upper end of the cable 26 is accommodated. The bore 40 terminates at its lower end in a bore 42 of larger cross-sectional dimensions than the bore 40, and in which the upper end of the tube 28 is accommodated in close tit. A resilient washer 43 is provided to ensure watertight sealing between the upper end of tube 28, cable 26 and bore 42. The grip element 38 is provided with a pair of intersecting slits 44 (see FIGURE 4) from the top and from the bottom, the slits of a pair being conveniently at right angles to one another, and dividing the top and bottom ends of the grip element 38 into four segments 50. Nuts 36a and 46, and lock nuts 48 are provided for tightening up the four segments 50 at the top and bottom ends of the grip element 38, for gripping the upper ends of the cable 26 and tube 28 in position.

It will be evident from the ydrawings that the pivotal mounting arrangement by way of the stirrup 32, links 34a and 34b, and yoke 36 permits linear yup and down reciprocal movement of the tube 28 and cable 26, regardless of irregular action of the actuating arm 12.

Connected to the lower end of cable 26 there is provided a pumping unit generally shown as 60 (see FIG- URE 5), which comprises a cylinder barrel 62 having a foot valve generally indicated as 64. The foot valve 64 comprises a perforated element 66, having a series of holes 68, and a valve closure member in the form of a at annular wafer-like member 70 which is seatable closably on the perforated element 66. Stop means in the form of a shoulder 72 is provided to limit the displacement of the valve closure member 70.

Within the cylinder barrel 62 there is accommodated a reciprocable member in the form of a hollow plunger 80, having a liquid ow passage 82 through it, and having at its lower end a non-return valve generally indicated as 84. The non-return valve 84 is of substantially the same construction as the foot valve 64, and comprises a perforated element 86 having holes 88, and a valve closure member 90, the displacement of which is -limited by the shoulder 92.

The upper end of the plunger is threaded as shown at 94 for connection to the cable 26, in similar fashion to that at the upper end. Outlet openings 96 are provided in the upper part of the plunger 80.

The plunger 80 is reciprocable in sealing relationship with the upper portion of the cylinder barrel 62, by way of sealing ring 98. The upper end of the cylinder barrel 62 is internally threaded as shown at 100, for connection to a delivery pipeline (not shown).

Bias means in the form of a compression coil spring 102 is provided to act upon the plunger 80 for urging it in the direction of its return stroke. The reciprocal movement of the plunger 80, in the downward direction, is limited by stop means in the form of cooperating shoulders on the plunger 80 and cylinder barrel 62, indicated as 104. In practice, the shoulder 104 will be well clear of the abutting shoulder during operation.

Resilient means (not shown), conveniently in the form of a tension coil spring, may be incorporated in the connecting means between threaded connection 94 and the actuating arm 12, for the purpose of damping shock loads on the cable 26 and the plunger 80 by reason of the action of the drive means 10. However, if a cable is used as the connecting means, the inherent resilience of the cable will be sufiicient to dampen shock loads, so that additional resilient means will not be required.

In operation, reciprocal movement is imparted to the plunger 80 via the drive means 10, the reciprocal movement being at a rate such that the acceleration of the plunger 80 on its return stroke is greater than the deceleration of the liquid being pumped, for example in the case of vertical pumping, the acceleration of the liquid when acted upon by gravity. This rate of reciprocation causes a substantially continuous flow of liquid to be created through the plunger 80, unlike the interrupted volumetric displacement of liquid hitherto obtained with reciprocating pumps.

Applicant has found that the use of opposing bias means shown in the drawings as 22 and 102 respectively, has the eect of lessening the power required to operate the pump, by counter-balancing the Weight of water in the delivery column and the weight of the dependent parts. The opposing bias means may be adjusted relatively to one another to suit varying operating conditions.

With the arrangement according to applicants invention, the reciprocable member may be advantageously arranged to have a comparatively small working stroke, say, of the order of about 1/2-1 inch. The applicant has also found that pumping rates of upward of one thousand strokes per minute, are possible. He has found further that the volume of water pumped can exceed the volume swept by the reciprocable element.

The actual length of stroke employed, the rate at which the reciprocable member is displaced, and the stiffness of the bias means may all be varied to suit varying circumstances.

I claim:

A reciprocating liquid pump which includes a reciprocable member adapted to permit liquid to pass through it during its reciprocation, drive means adapted to impart reciprocal movement to the reciprocable member at such a rate that its 4acceleration on its return stroke is greater than the deceleration of the liquid being pumped, connection means in the form of a flexible element selected from the group consisting of a cable and a wire for operatively connecting the drive means to the reciprocable member, and bias means to urge the reciprocable member in the direction of its return stroke and adapted to keep the flexible element under tension; the drive means being provided in a housing and comprising a bell-crank lever mounted for pivotal movement about an axis passing through its apex by way of a pin passing through its apex and journalled in the walls of the housing, an eccentric operatively connected to one arm of the bell-crank via a connecting link so as to impart reciprocal movement to that arm, the other arm of the bell-crank being connected operatively to the flexible connection means, and the eccentric being adapted to be driven by a prime mover; and in which there is further provided additional bias means to act between a w-all of the housing and an arm of the bell-crank to urge the bell-crank in the direction of the delivery stroke of the pump, to balance a delivery head.

References Cited by the Examiner UNITED STATES PATENTS 65,690 6/1867 Parks 103-212 1,922,121 8/1933 Brown 103-211 X 2,056,513 10/1936 Gambarini 103-76 2,632,401 3/1953 Mong 103--211 3,021,794 2/1962 Knox 103-212 X MARK NEWMAN, Primary Examiner.

WARREN E. COLEMAN, Examiner. 

